Does a good teacher necessarily have to be a creative teacher?
After a lifetime of being a teacher and being paid extra for being a really good one (A Master Teacher under the now discontinued Florida program - I was one until I retired) I can give a pretty positive answer to my own question:
A good teacher MUST be a creative teacher. He or she deals with many students each day, no two of which are identical in their learning process - even identical twins, of which I had a few pairs.
Just to attract and hold the attention of a class day after day demands creativity. To fit the subject to their needs and comprehension demands even more. In case you wonder, that's why American Education is in such a perpetual bind; a few dedicated creative people are attracted enough to become teachers but many (most) drop out after a few years because school and college administrators and overseers make creative teaching extremely difficult or impossible. There is never enough time to really develop an understanding and the pay really isn't enough to support a family the way a college-trained person want's their family to be supported.
For example, the public school year is 180 teaching days spread over the calendar year. (College years are even shorter). This is 20-30 or more days shorter than any other major developed nation. Why so short? My goodness, we'd have to pay the teachers and staff more and maintenance costs would go up.
Let's cut more into teaching time with tests to check and prove they aren't doing as well as we want and use that as an excuse for paying only some of them a little more each year, maybe they'll try harder next year. If they leave, well, we can hire new ones cheaper and maybe they'll do better.
We get what we pay for and we don't pay for creativity.

Onee, I tend to disagree with you about the ratio of talent to sweat especially in the field of painting.
Certainly a painter has to learn his craft - everything from draftsmanship to color balance and design (Draftsmanship is my particular bugaboo) but all the practice in the world will not make a good painting - there are lots of painters out there who are very elegant draftsmen, who make very bad paintings, and there are a very few, Picasso for example, who never took draftsmanship very seriously; but who were and are capable of making very very good paintings.
Unfortunately, we are coming out of an era (Pop Art, et al) where critics and dealers favored novelty over creativity. I don't care how well balanced they are, a painting of several superimposed squares or an enlarged comic strip panel ain't very creative, nor is it art. Neither is a large canvas (actually a large paper) full of silk-screened images of Marilyn Monroe, no matter how many different colors are sloppily applied.
On the other hand, I like Benton, Pollock, and Rauschenberg (among other modern painters).
Why and how do you suppose the un-talented manage to become so rich and famous while Van Gogh died in poverty?

It was my experience when teaching in Florida public schools, that the state tenure laws were much more protective of incompetent teachers than the teacher's union ever was. While the tenure laws have changed, they still make it difficult for a school system to rid itself of poor teachers.
This, however, is not by any means the reason school systems tolerate less than able teachers. The primary reason is that that's all they can get to fill vacancies. Most really good teachers who stay in teaching do it for the love of teaching - at least as long as they can afford to- but there are obviously never enough of them to go around.
For some years I supervised social studies teachers in a large public high school (3000+ students) and as a result I became , I think, more knowledgeable as well as a good deal more tolerant of teacher's abilities. Some I despised as incompetent when I started seemed to do very well if properly matched to their students and I had to watch many of the best and brightest drop out year after year as they no longer could afford to teach.
Early in my teaching career I was partially responsible for re-organizing a teachers union, I was trained in negotiating tactics at the U. of Chicago, and helped lead the only successful strike in Florida's history. I negotiated the largest percentage pay raise they ever (or probably will ever) get, Helped get a very large bond issue passed and ended with a commendation from the local school board. All in five years.
I know of no union protection of teachers that would prevent administrative evaluation - as long as that evaluation was fair, equitable, and based on evidence.
Teaching is one of the few professions where the government has tried to pay employees doing equal work different amounts based on conditions which neither the government or the teacher controls.
For example, here in FL, teacher pay is partially based on how well the students do on the F-CAT achievement tests, thinly disguised as "How much they have improved". Teachers at inner-city or rural schools serving predominately minority children have a much more difficult job than those in schools serving more affluent neighborhoods, but the latter are much more likely to receive the incentive pay. We tried moving the kids around to balance them out, but that raises all sorts of other problems, is expensive, and almost always means less public support for education, among other problems
If our educational system is to be improved, it will be very expensive - but worth it in the long run. Personally, I think the future of public education is on the internet with virtual interactive classrooms, while socialization and physical exercise is handled by neighborhood-based public athletic/interest organizations. The Soviet Union tried this separation system in their public schools for many years- it was about the only bright spot in their sad history, but we have a lot of evidence about how it worked.

Even current technology would allow for interactive individual teaching - and the way this is evolving, a virtual classroom fitted to the individual student is "about five minutes in the future"
As I suggested socialization and non-educational interests should be undertaken by a system set up to do that - Sort of a boys & girls club/scouts/ athletic/ interest - community based publicly funded organization. I mentioned the Soviet Union' s program because they carried this further than any other public system (Remember all those photos of the kids running around with red neckerchiefs?) and this was one of the few successful programs they had.
Their school system was fascinating but probably not appropriate to our needs. Yes, I studied this system fairly extensivly - at Harvard.

Maybe a return of the Draft?

I was at Harvard on a PhD program -I didn't stay long, as I decided to get married, buy a sailboat, and enjoy life.
My screen name is that of that sailboat - as is the icon. We celebrate our 44th anniversary in June.
Harvard wrote me for years asking where I was. I never had the heart to tell them I gave up higher ed for a sailboat.